Publications by authors named "Evan J Burke"
Article Synopsis
- - Hyoscyamine 6β-hydroxylase (H6H) is an enzyme that uses iron and 2-oxoglutarate to convert hyoscyamine into the antinausea drug scopolamine through a two-step process involving hydroxylation and epoxidation.
- - The enzyme first performs hydroxylation at the C6 position before coupling it to the C7 position, but the mechanism of how H6H prefers this route over simply hydroxylating at C7 is unclear.
- - Research shows that H6H does not rely on substrate positioning for epoxidation; instead, a small angle change in how the iron approaches the substrate influences whether it performs hydroxylation
Ethylene-forming enzyme (EFE) is an iron(II)-dependent dioxygenase that fragments 2-oxoglutarate (2OG) to ethylene (from C3 and C4) and 3 equivs of carbon dioxide (from C1, C2, and C5). This major ethylene-forming pathway requires l-arginine as the effector and competes with a minor pathway that merely decarboxylates 2OG to succinate as it oxidatively fragments l-arginine. We previously proposed that ethylene forms in a polar-concerted (Grob-like) fragmentation of a (2-carboxyethyl)carbonatoiron(II) intermediate, formed by the coupling of a C3-C5-derived propion-3-yl radical to a C1-derived carbonate coordinated to the Fe(III) cofactor.
View Article and Find Full Text PDFTET/JBP (ten-eleven translocation/base J binding protein) enzymes are iron(II)- and 2-oxo-glutarate-dependent dioxygenases that are found in all kingdoms of life and oxidize 5-methylpyrimidines on the polynucleotide level. Despite their prevalence, few examples have been biochemically characterized. Among those studied are the metazoan TET enzymes that oxidize 5-methylcytosine in DNA to hydroxy, formyl, and carboxy forms and the euglenozoa JBP dioxygenases that oxidize thymine in the first step of base J biosynthesis.
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